The 30-year-old model set off speculation Thursday in Los Angeles after she was spotted wearing an emerald and diamond ring on her left hand. The ring features an oval emerald surrounded by a circle of smaller diamonds.
Shayk and Cooper, 41, were first linked in spring 2015 following their respective splits from Cristiano Ronaldo and Suki Waterhouse. E! News reported in November that the model is pregnant and expecting their first child.
"Irina is feeling wonderful. She is so happy," a source told the website. "Bradley and her can't wait for their baby to arrive in the summer. They [also] know the sex of the baby."
"Bradley's mother [Gloria Campano] and Irina are very close, and she has been really supportive," the insider added. "She is ecstatic to be a grandma. She is a really kindhearted mom. They get along great -- even when Bradley is working they hang out."
"[Bradley] seems more protective of her," an insider said. "He has been spotted dropping her off at the airport with kisses as she is about to take off for another job. They are just a very sweet couple."